<s>
is	O
a	O
computer	B-General_Concept
operating	I-General_Concept
system	I-General_Concept
command	B-Application
which	O
is	O
used	O
to	O
bring	O
the	O
command	B-Application
line	O
on	O
top	O
of	O
the	O
computer	B-General_Concept
terminal	I-General_Concept
.	O
</s>
<s>
It	O
is	O
available	O
in	O
various	O
Unix	B-Application
shells	I-Application
on	O
Unix	B-Application
and	O
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
as	O
well	O
as	O
on	O
other	O
systems	O
such	O
as	O
KolibriOS	B-Operating_System
.	O
</s>
<s>
Depending	O
on	O
the	O
system	O
,	O
clear	O
uses	O
the	O
terminfo	B-Device
or	O
termcap	B-Application
database	O
,	O
as	O
well	O
as	O
looking	O
into	O
the	O
environment	O
for	O
the	O
terminal	B-General_Concept
type	O
in	O
order	O
to	O
deduce	O
how	O
to	O
clear	O
the	O
screen	O
.	O
</s>
<s>
The	O
Unix	B-Application
command	I-Application
clear	O
takes	O
no	O
arguments	O
and	O
is	O
roughly	O
analogous	O
to	O
the	O
command	B-Application
cls	O
on	O
a	O
number	O
of	O
other	O
operating	B-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
In	O
ISO	O
9995-7	O
specifies	O
that	O
the	O
following	O
symbol	O
be	O
used	O
to	O
indicate	O
this	O
function	O
on	O
a	O
keyboard	O
,	O
which	O
is	O
included	O
in	O
Unicode	O
as	O
:	O
⎚	B-Device
CLEAR	B-Device
SCREEN	I-Device
SYMBOL	O
.	O
</s>
<s>
One	O
may	O
use	O
the	O
reset	B-General_Concept
command	B-Application
to	O
erase	O
every	O
previous	O
command	B-Application
.	O
</s>
<s>
The	O
clear	O
command	B-Application
appeared	O
in	O
2.79BSD	O
on	O
February	O
24	O
,	O
1979	O
.	O
</s>
<s>
Later	O
,	O
in	O
1985	O
,	O
the	O
command	B-Application
was	O
also	O
included	O
in	O
Unix	B-Operating_System
8th	I-Operating_System
edition	I-Operating_System
.	O
</s>
